ECONOMICS OF AGROFORESTRY PRODUCTION IN IRRIGATED AGRICULTURE

摘要: A dynamic optimization model for agroforestry management is developed where tree biomass and soil salinity evolve over time in response to harvests irrigation water quantity quality. The applied production the San Joaquin Valley of California. Optimal applications are at first increasing salinity, then decreasing, while harvest decision relatively robust changes most underlying economic physical parameters. Drain reuse also appears promising: both net volumes implied returns substantial. Agroforestry a potential cropping system arid region irrigated agriculture. Agro- forestry arose as means commercial supply various products including hardwood furniture manufacture, other such pulp, new fuel source energy crisis 1970s (Lohr). Lohr performed an extensive insightful analysis this context. market was conducted California identifying likely prices received demand-related factors products. Data were collected from variety experi- mental plots, these used estimate growth function age factors. An identified efficient rotation levels, how they varied with distance center, spatial extent which could maintain positive returns. More recently, has been proposed one way managing drainage waters areas (San Drainage Program (SJVDP); Tanji Karajeh). Saline high tables emerge when deep percolation flows crop accumulate on impervious geologic strata. These occurrences can impact yields by reducing aeration rootzone. Historically, problems solved installation tile systems effluent disposal ocean or inland lakes, but increasingly circumscribed recognition environmental contaminants contained drain- waters. In approach management, saline gener- ated crops irrigate eucalyptus trees. Because